The management of the all the cages inside a facility is one of the largest problems that the facility manager (in charge of the laboratory technicians who manage the facility) has to address on a daily basis.
Knowing exactly how many cages are in use, in total, in the facility, how many cages are associated to a given owner (researcher, work area), exactly where they are located, for how long they have been in that position and tracking any previous positions are just some of the issues that the facility manager must address and resolve.
In fact, the laboratory technician must periodically carry out, on the cages in a facility, operations of management/maintenance of the cages and/or operations on the animal population inside the cage linked to the scientific research being conducted by the researcher. With regard to the cage, as known, the technician may periodically be required to carry out a full cage change, in which the animals are moved from the “soiled” cage to a new clean cage inclusive of new basin and new cover, or a partial cage change, in which only the basin is changed, naturally including the clean bedding, but not the cover.
To give an indication, procedures commonly require the laboratory technician to carry out a partial cage change, in which the basin with the bedding is changed, every two weeks, while three times out of four the cover is generally reused on the new tray. The cover of the tray is only replaced during the fourth basin change.
Therefore, the technician must track the content of a tray, i.e. the animals housed in the tray, also when a full or partial cage change is carried out and therefore the population of the cage is moved. It is also necessary to keep track of the movements that are carried out on the cages so that the exact position of each tray is known at all times.
Another common problem relates to management of the free spaces on the shelves of the facility that can be used for the management of incoming cages. Currently, when it is necessary to prepare new cages with animals, the facility manager must send the operators to find out where there are sufficient spaces available to house these cages, to be created subsequently. This entails a waste of time and resources that an automatic inventory system totally resolves.
In fact, it should always be borne in mind that large research centers of universities, hospitals and/or pharmaceutical companies have facilities with thousands of trays, and therefore a visual check by the operator of the spaces available on the shelves is neither easy nor immediate.
A further problem addressed by this invention is correct “billing” of the use of cages to the respective owners (essentially the researchers). Facility managers currently use more or less automatic software systems that require manual entry of the start and of the end of use of the cage due to conclusion of the test. If the system is not updated manually, calculation of the number of days that the researcher's cage occupied the shelf is inaccurate.
Although there are systems capable of performing inventory currently available on the market, they still require human intervention or, more generally, all have limitations that prevent the system from being fully automatic. Known solutions on the market are, for example, those in which a census of cages is carried out based on detection via a handheld RFID reader of the card holders with an RFID tag incorporated therein.
With a system of this kind, it is possible to know the number of cages and their position only when this information has been acquired (when the operator effectively walks around the rooms and scans the cages) and therefore has some evident limitations, such as not knowing whether the cage being scanned has always been in that position or if it was place there a few minutes earlier by someone else. More generically, solutions of this kind do not allow the movements of cages to be tracked inside the facility.
A further problem currently affecting facilities concerns the removal of cages by unauthorized personnel. With the current systems described, it is not possible to monitor whether a cage is removed and, moreover, cages can be removed by anyone.
In substance, with systems of this kind it is not possible to carry out an inventory/census in real time, but only partial and on request.
Moreover, the majority of systems that currently propose an inventory of the facility associate a tag with RFID (radio frequency identification) data transfer system with the card holder provided on the tray.
In this case there are two possibilities:
The RFID tag is incorporated in/attached to the card holder.
The RFID tag is the tag (card) that is inserted into the card holder containing all the information relating to the animals present in this cage.
There are some structural problems: when the technician carries out a full cage change, he/she cannot merely move the card from one card holder (soiled cage) to another (clean cage) but must also physically move the card holder with the tag included from the soiled cage to the clean cage in order for the information on the electronic system to remain coherent (or alternatively must record the new clean card holder in the system and eliminate the previous one).
The use of paper cards containing an RFID tag is a costly solution, as a new updated card must be used each time the conditions of the cage change and this change must be indicated (i.e. animals added/removed).
Moreover, neither of these solutions solves a problem of uniqueness of the content of the cage.
If the RFID card holder (or the RFID card itself) is confused or mixed with other similar card holders, containing the same general information on the animals (type, number and species), it will be impossible to trace it back to the exact origin without taking action on the animals, for example by comparing the unique ID of the animals (for example on the ear tag of the animal) with the ID associated to the RFID card holder (or indicated on the RFID card). Systems for inventory of the cages of a facility of the type discussed above are described, for example, in the prior art patent applications US 2012/0193415 A1 and WO 2012/051124.
Both these solutions essentially propose methods consisting of “tagging” the cage using RFID tags positioned directly on the cage.
Specifically, the solution proposed by US 2012/0193415 A1, fails to clearly describe a solution to the problem of how to incorporate the RFID label in the plastic tray, or of how to make it adhere permanently thereto. In fact, the tray is frequently autoclaved, so if this was a simple adhesive label, it would tend to be ineffective due to the numerous wash and autoclaving cycles to which the cage is subjected during its life. The fact of positioning the RFID label directly on the tray, on the basin or on the cover, has the drawback that at each cage change the data contained in the RFID label must be transferred to the new label incorporated in or attached to the tray. Moreover, this patent does not describe an automatic reading system of the RFID label, which is presumed to take place through a manual reading system, such as a handheld reader
Instead, with regard to the patent WO2012/051124, as this refers to a disposable cage (which is therefore not washed and autoclaved as it is disposed of after around 10/14 days of use), the operator requires to carry out a time-consuming (and costly) operation each time to attach a new RFID adhesive label to the new cage to be used for the same animals being used in the experiment (every 10/14 days the cage must be replaced with a new one with clean bedding, the information on the cage must be transferred from the soiled cage to the clean cage, remaining coherent), and to transfer the data from the old label to the new one.